Lots of cotton cloth of the type that you can find at yardage stores, has an additive, which is commonly called "sizing", added to the cloth at the manufacturer. This stuff helps to keep the cloth flat and easy to cut when making sewn patterns and it adds stiffness to the cotton weave.

A washing, or two, in normal soap and water in the everyday washing machine will reduce the sizing considerably and give the cloth much better drape over irregular surfaces.

Cut the cloth extra big for the area you wish to cover on the boat, etc. Run it through a sewing machine to establish a hard perimeter so it won't unravel and wash it a time or two. Iron the wrinkles out of the fabric prior to use and it will drape much more easily. It can also help to cut the cloth so that the hardest curves are being addressed by the fabric on the bias, rather than the warp or weft of the weave.

The weight of the cloth will also present its own special issues with lighter weight fabrics being easier to conform to the surface, but they hold less detail in the print.

Practice with scraps before you commit to the real thing.

I made a lot of custom surfboards with wacky cloth laminates way back
when.